The present invention provides a method and system for re-ranking search results in a patent retrieval system where the query text is derived in whole or in part from a patent claim, which may be from an existing patent or a prospective claim. The re-ranking is based on several features of the candidate patent, such as the text similarity to the claim, international patent code or other classification or subject matter relatedness or overlap, and internal citation structure of the candidates. One alternative aspect provides a re-ranker that is trained on automatically generated training data, thus obviating the expensive and time-intensive step of expert annotation.